Multi-read sensor having a narrow read gap structure

ABSTRACT

In one embodiment, a magnetic head includes at least one magnetoresistive (MR) element positioned at a media-facing surface of the magnetic head, a lower portion of the at least one MR element extending in an element height direction away from the media-facing surface of the magnetic head farther than an upper portion of the at least one MR element, at least one back wiring layer positioned behind the upper portion of the at least one MR element in the element height direction and above the lower portion of the at least one MR element, the at least one back wiring layer being configured to electrically communicate with the at least one MR element, and an upper wiring layer positioned above the at least one MR element at the media-facing surface of the magnetic head and extending in the element height direction away from the media-facing surface of the magnetic head.

RELATED APPLICATIONS

This application is a continuation of U.S. patent application Ser. No.14/085,734, filed Nov. 20, 2013, which is herein incorporated byreference.

FIELD OF THE INVENTION

The present invention relates to magnetic heads, and more particularly,this invention relates to a magnetic head having a multi-read sensorwith a narrow read gap structure.

BACKGROUND

The heart of a computer is a magnetic hard disk drive (HDD) whichtypically includes a rotating magnetic disk, a slider that has read andwrite heads, a suspension arm above the rotating disk and an actuatorarm that swings the suspension arm to place the read and/or write headsover selected circular tracks on the rotating disk. The suspension armbiases the slider into contact with the surface of the disk when thedisk is not rotating but, when the disk rotates, air is swirled by therotating disk adjacent an air bearing surface (ABS) of the slidercausing the slider to ride on an air bearing a slight distance from thesurface of the rotating disk. When the slider rides on the air bearingthe write and read heads are employed for writing magnetic impressionsto and reading magnetic signal fields from the rotating disk. The readand write heads are connected to processing circuitry that operatesaccording to a computer program to implement the writing and readingfunctions.

The volume of information processing in the information age isincreasing rapidly. In particular, HDDs have been desired to store moreinformation in its limited area and volume. A technical approach to thisdesire is to increase the capacity by increasing the recording densityof the HDD. To achieve higher recording density, further miniaturizationof recording bits is effective, which in turn typically requires thedesign of smaller and smaller components.

Magnetoresistive effect type magnetic heads are employed as sensors forreading magnetic information (data) recorded on a magnetic recordingmedium (such as a hard disk) in high-density magnetic recording devices(such as HDDs). The use of magnetic read heads that utilize amagnetoresistive effect has become commonplace. One suchmagnetoresistive effect type read head uses a giant magnetoresistive(GMR) effect in a multi-layered film formed by laminating aferromagnetic metal layer on a non-magnetic intermediate layer. Thefirst kind of GMR heads employed were Current-In-Plane (CPP)-type headsin which electrical signals flow in parallel with the film plane to thesensor membrane. Next, Tunneling Magnetoresistive (TMR)-effect heads andCurrent-Perpendicular-To-Plane (CPP)-GMR heads, which are consideredadvantageous from the standpoint of track narrowing, gap narrowing, andincreased output, were developed with improved recording density inmind. TMR heads are now the most commonly employed magnetic read head.TMR heads and CPP-GMR heads differ from conventional GMR heads, theydiffer significantly from CIP-type heads, and they differ from CPP-typeheads.

While the demand in recent years for even higher density recording hasbeen met by techniques based on narrowing the effective track width of amagnetoresistive sensor, this track width narrowing has resulted inother problems of increased element resistance, increased noise, loweredsensitivity, and difficulties in increasing the sensitivity.

Multi-element magnetic heads designed to accommodate higher densityrecording have been proposed to alleviate these problems. Multi-elementmagnetic heads are advantageous in that they comprise a magnetic headwith a large number of elements of a size greater than a bit size of themedium, and this allows for bit data to be read from the difference inthe plurality of signals produced thereby. Because the element size maybe increased beyond a single bit size, noise is able to be suppressedand sensitivity is able to be increased.

One such multi-element magnetic head 50 is shown from a media-facingsurface in FIG. 5A and from a side view in FIG. 5B and according to theprior art. An inherent problem in the multi-element read head 50 is thatalthough it allows for the formation of each element 4, 5 to have a sizegreater than a recording bit size, the inter-shield distance (alsoreferred to as the read gap width, which is the distance between thelower magnetic shield layer 1 and the upper magnetic shield layer 16 inthe head 50) is expanded because of the arrangement of a first wiringlayer 10 and a second wiring layer 11 which are configured forseparately extracting signals from their respective elements, firstelement 4 and second element 5. The multi-element read head 50 alsoincludes an insulating layer 21 positioned behind the MR elements 4, 5,a magnetic domain control layer 7 disposed therebetween and on bothsides of the MR elements 4, 5, and an insulating layer 6 between theupper magnetic shield layer 16 and the first wiring layer 10 and thesecond wiring layer 11.

SUMMARY

In one embodiment, a magnetic head includes at least onemagnetoresistive (MR) element, the at least one MR element extending inan element height direction away from a media-facing surface of themagnetic head, and at least one back wiring layer positioned above atleast one lower layer of the at least one MR element at a position awayfrom the media-facing surface of the magnetic head in the element heightdirection, wherein the at least one back wiring layer is configured toelectrically communicate with the at least one MR element.

In another embodiment, a magnetic head includes at least one MR elementpositioned at a media-facing surface of the magnetic head, a lowerportion of the at least one MR element extending in an element heightdirection away from the media-facing surface of the magnetic headfarther than an upper portion of the at least one MR element, at leastone back wiring layer positioned behind the upper portion of the atleast one MR element in the element height direction and above the lowerportion of the at least one MR element, wherein the at least one backwiring layer is configured to electrically communicate with the at leastone MR element, and an upper wiring layer positioned above the at leastone MR element at the media-facing surface of the magnetic head andextending in the element height direction away from the media-facingsurface of the magnetic head, the upper wiring layer being configured toelectrically communicate with the back wiring layer.

In yet another embodiment, a method for forming a magnetic head includesforming at least one MR element, the at least one MR element extendingin an element height direction away from a media-facing surface of themagnetic head, and forming at least one back wiring layer positionedabove at least one lower layer of the at least one MR element at aposition away from the media-facing surface of the magnetic head in theelement height direction, wherein the at least one back wiring layer isconfigured to electrically communicate with the at least one MR element.

Any of these embodiments may be implemented in a magnetic data storagesystem such as a disk drive system, which may include a magnetic head, adrive mechanism for passing a magnetic medium (e.g., hard disk) over themagnetic head, and a controller electrically coupled to the magnetichead.

Other aspects and advantages of the present invention will becomeapparent from the following detailed description, which, when taken inconjunction with the drawings, illustrate by way of example theprinciples of the invention.

BRIEF DESCRIPTION OF THE DRAWINGS

For a fuller understanding of the nature and advantages of the presentinvention, as well as the preferred mode of use, reference should bemade to the following detailed description read in conjunction with theaccompanying drawings.

FIG. 1 is a simplified drawing of a magnetic recording disk drivesystem.

FIG. 2A is a schematic representation in section of a recording mediumutilizing a longitudinal recording format.

FIG. 2B is a schematic representation of a conventional magneticrecording head and recording medium combination for longitudinalrecording as in FIG. 2A.

FIG. 2C is a magnetic recording medium utilizing a perpendicularrecording format.

FIG. 2D is a schematic representation of a recording head and recordingmedium combination for perpendicular recording on one side.

FIG. 2E is a schematic representation of a recording apparatus adaptedfor recording separately on both sides of the medium.

FIG. 3A is a cross-sectional view of one particular embodiment of aperpendicular magnetic head with helical coils.

FIG. 3B is a cross-sectional view of one particular embodiment of apiggyback magnetic head with helical coils.

FIG. 4A is a cross-sectional view of one particular embodiment of aperpendicular magnetic head with looped coils.

FIG. 4B is a cross-sectional view of one particular embodiment of apiggyback magnetic head with looped coils.

FIG. 5A shows a multi-element magnetoresistive (MR) read head accordingto the prior art as seen from a media-facing surface thereof.

FIG. 5B shows a side view of a multi-element magnetic head according tothe prior art.

FIG. 6A shows a multi-element magnetic head according to one embodimentas seen from a media-facing surface thereof

FIG. 6B shows a side view of a multi-element magnetic head according toone embodiment.

FIGS. 7A-7H show various structures formed in a method for manufacturinga multi-element magnetic head according to one embodiment.

FIGS. 8A-8H show various structures formed in a method for manufacturinga multi-element magnetic head according to another embodiment.

FIGS. 9A-9H show various structures formed in a method for manufacturinga multi-element magnetic head according to yet another embodiment.

FIGS. 10A-10G show various structures formed in a method formanufacturing a multi-element magnetic head in another embodiment.

FIGS. 11A-11G show various structures formed in a method formanufacturing a multi-element magnetic head according to anotherembodiment.

FIGS. 12A-12G show various structures formed in a method formanufacturing a multi-element magnetic head according to anotherembodiment.

DETAILED DESCRIPTION

The following description is made for the purpose of illustrating thegeneral principles of the present invention and is not meant to limitthe inventive concepts claimed herein. Further, particular featuresdescribed herein can be used in combination with other describedfeatures in each of the various possible combinations and permutations.

Unless otherwise specifically defined herein, all terms are to be giventheir broadest possible interpretation including meanings implied fromthe specification as well as meanings understood by those skilled in theart and/or as defined in dictionaries, treatises, etc.

It must also be noted that, as used in the specification and theappended claims, the singular forms “a,” “an” and “the” include pluralreferents unless otherwise specified.

The following description discloses several preferred embodiments ofdisk-based storage systems and/or related systems and methods, as wellas operation and/or component parts thereof.

According to one embodiment, the signals may be separately extractedfrom multiple elements in a multi-element read head by extracting eachof the signals using a wire in the element height direction.Furthermore, a desired narrowing of the read gap width may befacilitated along with a desired increase in the recording density ofthe media without increasing noise significantly.

In one general embodiment, a magnetic head includes a lower shield layerpositioned at a media-facing surface of the magnetic head, at least twomagnetoresistive (MR) elements positioned above the lower shield layer,each MR element extending in an element height direction away from themedia-facing surface of the magnetic head, back wiring layers positionedabove at least one lower layer of each of the MR elements at a positionaway from the media-facing surface of the magnetic head in the elementheight direction, wherein the back wiring layers are configured toelectrically communicate with the MR elements and configured toseparately extract signals from each MR element during a read operation,and an upper shield layer positioned above the MR elements that isconfigured to electrically communicate with the MR elements.

In another general embodiment, a magnetic head includes a lower shieldlayer positioned at a media-facing surface of the magnetic head, atleast two MR elements positioned above the lower shield layer, each MRelement extending in an element height direction away from themedia-facing surface of the magnetic head, back wiring layers positionedabove at least one lower layer of each of the MR elements at a positionaway from the media-facing surface of the magnetic head in the elementheight direction, wherein the back wiring layers are configured toelectrically communicate with the MR elements and configured toseparately extract signals from each MR element during a read operation,and an upper wiring layer positioned above each MR element at themedia-facing surface of the magnetic head and extending in the elementheight direction away from the media-facing surface of the magnetichead, the upper wiring layer being configured to electricallycommunicate with the back wiring layer, wherein the upper wiring layeris configured to act as an upper electrode for the MR elements, andwherein the lower shield layer is configured to act as a lower electrodefor the MR elements.

In yet another general embodiment, a method for forming a magnetic headincludes forming a lower shield layer, forming at least two MR elementspositioned above the lower shield layer at a media-facing surface of themagnetic head, each MR element extending in an element height directionaway from the media-facing surface of the magnetic head, forming a backwiring layer positioned above the at least two MR elements at a positionaway from the media-facing surface of the magnetic head in the elementheight direction, wherein the back wiring layer is configured toelectrically communicate with the at least two MR elements andconfigured to separately extract signals from each MR element during aread operation, and forming an upper shield layer positioned above theat least two MR elements and configured to electrically communicate withthe at least two MR elements, wherein the upper shield layer isconfigured to act as an upper electrode for the at least two MRelements.

Referring now to FIG. 1, there is shown a disk drive 100 in accordancewith one embodiment of the present invention. As shown in FIG. 1, atleast one rotatable magnetic disk 112 is supported on a spindle 114 androtated by a drive mechanism, which may include a disk drive motor 118.The magnetic recording on each disk is typically in the form of anannular pattern of concentric data tracks (not shown) on the disk 112.

At least one slider 113 is positioned near the disk 112, each slider 113supporting one or more magnetic read/write heads 121. As the diskrotates, slider 113 is moved radially in and out over disk surface 122so that heads 121 may access different tracks of the disk where desireddata are recorded and/or to be written. Each slider 113 is attached toan actuator arm 119 by means of a suspension 115. The suspension 115provides a slight spring force which biases slider 113 against the disksurface 122. Each actuator arm 119 is attached to an actuator 127. Theactuator 127 as shown in FIG. 1 may be a voice coil motor (VCM). The VCMcomprises a coil movable within a fixed magnetic field, the directionand speed of the coil movements being controlled by the motor currentsignals supplied by controller 129.

During operation of the disk storage system, the rotation of disk 112generates an air bearing between slider 113 and disk surface 122 whichexerts an upward force or lift on the slider. The air bearing thuscounter-balances the slight spring force of suspension 115 and supportsslider 113 off and slightly above the disk surface by a small,substantially constant spacing during normal operation. Note that insome embodiments, the slider 113 may slide along the disk surface 122.

The various components of the disk storage system are controlled inoperation by control signals generated by controller 129, such as accesscontrol signals and internal clock signals. Typically, control unit 129comprises logic control circuits, storage (e.g., memory), and amicroprocessor. The control unit 129 generates control signals tocontrol various system operations such as drive motor control signals online 123 and head position and seek control signals on line 128. Thecontrol signals on line 128 provide the desired current profiles tooptimally move and position slider 113 to the desired data track on disk112. Read and write signals are communicated to and from read/writeheads 121 by way of recording channel 125.

The above description of a typical magnetic disk storage system, and theaccompanying illustration of FIG. 1 is for representation purposes only.It should be apparent that disk storage systems may contain a largenumber of disks and actuators, and each actuator may support a number ofsliders.

An interface may also be provided for communication between the diskdrive and a host (integral or external) to send and receive the data andfor controlling the operation of the disk drive and communicating thestatus of the disk drive to the host, all as will be understood by thoseof skill in the art.

In a typical head, an inductive write head includes a coil layerembedded in one or more insulation layers (insulation stack), theinsulation stack being located between first and second pole piecelayers. A gap is formed between the first and second pole piece layersby a gap layer at an air bearing surface (ABS) of the write head. Thepole piece layers may be connected at a back gap. Currents are conductedthrough the coil layer, which produce magnetic fields in the polepieces. The magnetic fields fringe across the gap at the ABS for thepurpose of writing bits of magnetic field information in tracks onmoving media, such as in circular tracks on a rotating magnetic disk.

The second pole piece layer has a pole tip portion which extends fromthe ABS to a flare point and a yoke portion which extends from the flarepoint to the back gap. The flare point is where the second pole piecebegins to widen (flare) to form the yoke. The placement of the flarepoint directly affects the magnitude of the magnetic field produced towrite information on the recording medium.

FIG. 2A illustrates, schematically, a conventional recording medium suchas used with magnetic disc recording systems, such as that shown inFIG. 1. This medium is utilized for recording magnetic impulses in orparallel to the plane of the medium itself. The recording medium, arecording disc in this instance, comprises basically a supportingsubstrate 200 of a suitable non-magnetic material such as glass, with anoverlying coating 202 of a suitable and conventional magnetic layer.

FIG. 2B shows the operative relationship between a conventionalrecording/playback head 204, which may preferably be a thin film head,and a conventional recording medium, such as that of FIG. 2A.

FIG. 2C illustrates, schematically, the orientation of magnetic impulsessubstantially perpendicular to the surface of a recording medium as usedwith magnetic disc recording systems, such as that shown in FIG. 1. Forsuch perpendicular recording the medium typically includes an underlayer 212 of a material having a high magnetic permeability. This underlayer 212 is then provided with an overlying coating 214 of magneticmaterial preferably having a high coercivity relative to the under layer212.

FIG. 2D illustrates the operative relationship between a perpendicularhead 218 and a recording medium. The recording medium illustrated inFIG. 2D includes both the high permeability under layer 212 and theoverlying coating 214 of magnetic material described with respect toFIG. 2C above. However, both of these layers 212 and 214 are shownapplied to a suitable substrate 216. Typically there is also anadditional layer (not shown) called an “exchange-break” layer or“interlayer” between layers 212 and 214.

In this structure, the magnetic lines of flux extending between thepoles of the perpendicular head 218 loop into and out of the overlyingcoating 214 of the recording medium with the high permeability underlayer 212 of the recording medium causing the lines of flux to passthrough the overlying coating 214 in a direction generally perpendicularto the surface of the medium to record information in the overlyingcoating 214 of magnetic material preferably having a high coercivityrelative to the under layer 212 in the form of magnetic impulses havingtheir axes of magnetization substantially perpendicular to the surfaceof the medium. The flux is channeled by the soft underlying coating 212back to the return layer (P1) of the head 218.

FIG. 2E illustrates a similar structure in which the substrate 216carries the layers 212 and 214 on each of its two opposed sides, withsuitable recording heads 218 positioned adjacent the outer surface ofthe magnetic coating 214 on each side of the medium, allowing forrecording on each side of the medium.

FIG. 3A is a cross-sectional view of a perpendicular magnetic head. InFIG. 3A, helical coils 310 and 312 are used to create magnetic flux inthe stitch pole 308, which then delivers that flux to the main pole 306.Coils 310 indicate coils extending out from the page, while coils 312indicate coils extending into the page. Stitch pole 308 may be recessedfrom the ABS 318. Insulation 316 surrounds the coils and may providesupport for some of the elements. The direction of the media travel, asindicated by the arrow to the right of the structure, moves the mediapast the lower return pole 314 first, then past the stitch pole 308,main pole 306, trailing shield 304 which may be connected to the wraparound shield (not shown), and finally past the upper return pole 302.Each of these components may have a portion in contact with the ABS 318.The ABS 318 is indicated across the right side of the structure.

Perpendicular writing is achieved by forcing flux through the stitchpole 308 into the main pole 306 and then to the surface of the diskpositioned towards the ABS 318.

FIG. 3B illustrates a piggyback magnetic head having similar features tothe head of FIG. 3A. Two shields 304, 314 flank the stitch pole 308 andmain pole 306. Also sensor shields 322, 324 are shown. The sensor 326 istypically positioned between the sensor shields 322, 324.

FIG. 4A is a schematic diagram of one embodiment which uses looped coils410, sometimes referred to as a pancake configuration, to provide fluxto the stitch pole 408. The stitch pole then provides this flux to themain pole 406. In this orientation, the lower return pole is optional.Insulation 416 surrounds the coils 410, and may provide support for thestitch pole 408 and main pole 406. The stitch pole may be recessed fromthe ABS 418. The direction of the media travel, as indicated by thearrow to the right of the structure, moves the media past the stitchpole 408, main pole 406, trailing shield 404 which may be connected tothe wrap around shield (not shown), and finally past the upper returnpole 402 (all of which may or may not have a portion in contact with theABS 418). The ABS 418 is indicated across the right side of thestructure. The trailing shield 404 may be in contact with the main pole406 in some embodiments.

FIG. 4B illustrates another type of piggyback magnetic head havingsimilar features to the head of FIG. 4A including a looped coil 410,which wraps around to form a pancake coil. Also, sensor shields 422, 424are shown. The sensor 426 is typically positioned between the sensorshields 422, 424.

In FIGS. 3B and 4B, an optional heater is shown near the non-ABS side ofthe magnetic head. A heater (Heater) may also be included in themagnetic heads shown in FIGS. 3A and 4A. The position of this heater mayvary based on design parameters such as where the protrusion is desired,coefficients of thermal expansion of the surrounding layers, etc.

FIG. 6A shows a multi-element magnetic read head 60 as seen from amedia-facing surface of the head, such as an ABS thereof, according toone embodiment. FIG. 6B shows a side view of the multi-element magneticread head 60 according to the embodiment.

According to one embodiment, the problems described above in relation toFIGS. 5A-5B may be overcome using the head 60 as shown in FIGS. 6A-6B.This head 60 comprises an insulating layer 14 that is positioned above(but not necessarily directly on) a lower magnetic shield layer 1. Afirst magnetoresistive (MR) read element 4 and a second MR read element5 are positioned above (but not necessarily directly on) the insulatinglayer 14, and a refill layer 6 is positioned on both sides of the firstMR read element 4 and on both sides of the second MR read element 5.Furthermore, a portion of the first MR read element 4 and a portion ofthe second MR read element 5 extend along an element height direction 25perpendicular to the media-facing surface toward a rear side thereof toconnect with back wiring layers 20, which are positioned near rear sidesof at least one lower layer of each MR read element 4, 5. The lowerlayer(s) can be any layer(s) below the reference layer (pinned layer).For example, a lower layer may be a seed layer, an antiferromagneticlayer, etc. Such lower layer may extend beyond the back edge 61 of thefree layer (and potentially other layers) of the associated MR elementin the element height direction 25. Thus, the back wiring layers 20 areconfigured to electrically communicate with the associated MR element 4,5 and configured to separately extract signals from each MR element 4, 5during a read operation. The magnetic data storage system may includeseparate processing channels for each of the wiring layers 20, therebyenabling separate processing of signals from each MR element.

Because the head 60 positions the back wiring layers 20 on a rear sideof the elements 4, 5, the back wiring layers 20 are not exposed at themedia-facing surface of the head 60, which provides additionalprotection to these layers. This arrangement also allows for a narrowingof the read gap thickness, along with a narrowing of a thickness of theback wiring layers 20. These advancements allow for the head 60 to readdata from a magnetic medium having an increased recording density ascompared to conventional magnetic media.

In some approaches, a multi-element magnetic read head 60 as shown inFIGS. 6A-6B may be used in a magnetic data storage system. The magneticdata storage system may be similar to that shown in FIG. 1. For example,the magnetic data storage system 100 may comprise at least one magnetichead 121 as described according to any embodiment herein, a magneticmedium 112, a drive mechanism 118 for passing the magnetic medium 112over the at least one magnetic head 121, and a controller 129electrically coupled to the at least one magnetic head 121 forcontrolling operation of the at least one magnetic head 121.

With reference to FIGS. 7A-7H, a method for manufacturing amulti-element magnetic read head is shown in various states of formationaccording to one embodiment. This method includes a step for fabricatinga lower magnetic shield layer 1, a step for fabricating an insulatinglayer 14 above the lower magnetic shield layer 1, a step for fabricatinga MR film 2 above the insulating layer 14, a step for fabricating atrack pattern mask 3 above the MR film 2, a step for etching the MR film2, a step for laminating a refill layer 6 with a magnetic domain controllayer 7 while the track pattern mask 3 is still held in place followedby removing the track pattern mask 3, a step for etching the MR film 2to a barrier layer in order to fabricate a height pattern mask 13, astep for laminating a height refill layer 21 with the height maskpattern 13 still held in place followed by removing the height maskpattern 13, a step for removing a portion of the height refill layer 21to fabricate a back wiring layer 20, and a step for fabricating an uppermagnetic shield layer 16.

Each step will be described with reference to one or more Figures, eachFigure including a view from the media-facing surface of the structureon the left, and a cross-sectional side view of the structure on theright.

With reference to FIG. 7A, a lower magnetic shield layer 1 comprisingNiFe, CoFe, or some other suitable material known in the art isprovided. The lower magnetic shield layer 1 may be provided by way of afilm of Al₂O₃, MgO, etc., on an Al₂O₃—TiC wafer serving as a base bodyof a slider (not shown in the Figures). Then, for example, a sputteringmethod or some other suitable formation technique may be employed todeposit an insulating layer 14 comprising Al₂O₃ (alumina) or some othersuitable insulting material thereon. The insulating layer 14 may have athickness, in some approaches, in a range from about 1 nm to about 10nm, such as about 2 nm.

Next, a sputtering method or some other suitable formation technique maybe employed to fabricate a MR film 2 thereabove. The MR film 2 maycomprise any layers and materials known in the art. In one example, theMR film 2 may comprise at least a free layer, a barrier layer, and apinned layer. More specifically, the MR film 2 may comprise, forexample, a 1 nm Ta underlayer, a 5 nm IrMn antiferromagnetic (AFM)layer, a 2 nm CoFeB pinned layer, a MgO tunnel insulating film, and afree layer comprising a 5 nm CoFeB/2 nm NiFe laminated film.

Next, as shown in FIG. 7B, a track pattern mask 3 is provided to form agap between later-formed elements. The track pattern mask extends fullfilm in the element height direction. The gap may be about equal to atrack width, such as from about 5 nm to about 30 nm. For example, a 20nm track width may be fabricated in the MR film 2 by spacer-type doublepatterning or some other suitable method known in the art. In thespacer-type double patterning, an ArF exposure apparatus, an ArF liquidimmersion exposure apparatus, or extreme ultraviolet lithography (EUV)may be utilized, along with a normal exposure and/or double patterning.

Next, as shown in FIG. 7C, using the track pattern mask 3 as a mask, theMR film 2 is etched using any suitable etching technique known in theart, such as via Ar ion milling, reactive ion etching (RIE), etc., toexpose the insulating layer 14 and fabricate a first MR element 4 and asecond MR element 5 which comprise portions of the MR film 2 whichremains after the etching process. The upper magnetic shield layer 16 isconfigured to electrically communicate with the MR elements 4, 5, in oneembodiment.

Then, a refill layer 6 is formed using any suitable formation technique,such as a sputtering method. The refill layer 6 may have a thickness ina range from about 1 nm to about 30 nm, such as about 2 nm. Furthermore,the refill layer may comprise any suitable material, such as Al₂O₃, MgO,etc. Then, a magnetic domain control layer 7 is deposited using anysuitable deposition method, such as a long throw sputtering (LTS) methodhaving excellent linearity, to a thickness in a range from about 5 nm toabout 100 nm, such as about 13 nm. The magnetic domain control layer 7may comprise any suitable material known in the art, such as CoPt amongothers.

Next, as shown in FIG. 7D, the track pattern mask 3 is removed bylift-off, chemical mechanical polishing (CMP) or some other suitabletechnique known in the art.

As shown in FIG. 7E, a height mask pattern 13 is provided above thefirst MR element 4 and the second MR element 5 to establish a heightfrom the media-facing surface in the element height direction in a rangefrom about 50 nm to about 1000 nm, such as about 500 nm. This heightmask pattern 13 is used as a mask to etch the magnetic domain controllayer 7, the refill layer 6, and the two elements 4, 5 using Ar ionmilling, RIE, or some other suitable technique, to expose the pinnedlayer of the elements 4, 5.

Next, as shown in FIG. 7F, a refill layer 21 is deposited above theetched portions of the structure using any technique known in the art,such as a sputtering method, to a thickness in a range from about 5 nmto about 30 nm, such as about 20 nm, which may comprise any suitablematerial known in the art, such as Al₂O₃. Then the height mask pattern13 is removed by lift-off, CMP, etc. The refill layer 21 may be formedof the same material as refill layer 6, and may form a continuous refilllayer between the various components of the head, in one approach.

As shown in FIG. 7G, a wiring mask pattern is formed above the structureat the media-facing surface thereof, and some of the height refill layer21 is removed via etching at a rear end thereof in the element heightdirection, such as via Ar ion milling. Then, a back wiring layer 20 isformed behind the refill layer 21 in the element height direction usingany suitable method known in the art from a suitable conductivematerial, such as Au, Ag, etc., to a thickness in a range between about5 nm to about 100 nm, such as about 100 nm.

Then, as shown in FIG. 7H, a sputtering method is used to form an uppermagnetic shield layer 16 and an additional insulating layer (alsolabeled as 21) between the back wiring layer 20 and the upper magneticshield layer 16. Any suitable materials may be used for the uppermagnetic shield layer 16 and additional insulating layer as known in theart.

The method described in FIGS. 7A-7H is representative of the formationof one embodiment of a multi-element magnetic head. Although twoelements 4, 5 are shown, it is possible to form more than two elementsin each read head, as would be understood by one of skill in the art,such as three four, 10, 16, 24, 32, etc.

According to another embodiment, a magnetic head may be formed inaccordance with a method described with reference to FIGS. 8A-8H.

As shown in FIG. 8A, a lower magnetic shield layer 1 comprising NiFe,CoFe, or some other suitable material known in the art is provided. Thelower magnetic shield layer 1 may be provided by way of a film of Al₂O₃,MgO, etc., on an Al₂O₃—TiC wafer serving as a base body of a slider (notshown in the Figures). Then, for example, a sputtering method or someother suitable formation technique may be employed to deposit aninsulating layer 14 comprising alumina or some other suitable insultingmaterial thereon. The insulating layer 14 may have a thickness, in someapproaches, in a range from about 1 nm to about 10 nm, such as about 2nm. Next, wiring underlayer 18 is formed using any suitable formationtechnique known in the art, such as sputtering, to a thickness ofbetween about 1 nm and about 10 nm, for example, 5 nm, which maycomprise any suitable material, such as Cr.

Next, a sputtering method or some other suitable formation technique maybe employed to fabricate a MR film 2 thereabove. The MR film 2 maycomprise any layers and materials known in the art. In one example, theMR film 2 may comprise at least a free layer, a barrier layer, and apinned layer. More specifically, the MR film 2 may comprise, forexample, a 1 nm Ta underlayer, a 5 nm IrMn AFM layer, a 2 nm CoFeBpinned layer, a MgO tunnel insulating film, and a free layer comprisinga 5 nm CoFeB/2 nm NiFe laminated film.

Next, as shown in FIG. 8B, a track pattern mask 3 is provided to form agap between later-formed elements. The track pattern mask extends fullfilm in the element height direction. The gap may be about equal to atrack width, such as from about 5 nm to about 30 nm. For example, a 20nm track width may be fabricated in the MR film 2 by spacer-type doublepatterning or some other suitable method known in the art. In thespacer-type double patterning, an ArF exposure apparatus, an ArF liquidimmersion exposure apparatus, or EUV may be utilized, along with anormal exposure and/or double patterning.

Next, as shown in FIG. 8C, using the track pattern mask 3 as a mask, theMR film 2 is etched using any suitable etching technique known in theart, such as via Ar ion milling, RIE, etc., to expose the insulatinglayer 14 and fabricate a first MR element 4 and a second MR element 5which comprise portions of the MR film 2 which remains after the etchingprocess.

Then, a refill layer 6 is formed using any suitable formation technique,such as a sputtering method. The refill layer 6 may have a thickness ina range from about 1 nm to about 30 nm, such as about 2 nm. Furthermore,the refill layer may comprise any suitable material, such as Al₂O₃, MgO,etc. Then, a magnetic domain control layer 7 is deposited using anysuitable deposition method, such as a LTS method having excellentlinearity, to a thickness in a range from about 5 nm to about 100 nm,such as about 13 nm. The magnetic domain control layer 7 may compriseany suitable material known in the art, such as CoPt among others.

Next, as shown in FIG. 8D, the track pattern mask 3 is removed bylift-off, CMP or some other suitable technique known in the art.

As shown in FIG. 8E, a height mask pattern 13 is provided above thefirst MR element 4 and the second MR element 5 to establish a heightfrom the media-facing surface in the element height direction in a rangefrom about 50 nm to about 1000 nm, such as about 500 nm. This heightmask pattern 13 is used as a mask to etch the magnetic domain controllayer 7, the refill layer 6, and the two elements 4, 5 using Ar ionmilling, RIE, or some other suitable technique, to expose the pinnedlayer of the elements 4, 5.

Next, as shown in FIG. 8F, a refill layer 21 is deposited above theetched portions of the structure using any technique known in the art,such as a sputtering method, to a thickness in a range from about 5 nmto about 30 nm, such as about 20 nm, which may comprise any suitablematerial known in the art, such as Al₂O₃. Then the height mask pattern13 is removed by lift-off, CMP, etc.

As shown in FIG. 8G, a wiring mask pattern is formed above the structureat the media-facing surface thereof, and some of the height refill layer21 is removed via etching at a rear end thereof in the element heightdirection, such as via Ar ion milling. Then, a back wiring layer 20 isformed behind the refill layer 21 in the element height direction usingany suitable method known in the art from a suitable conductivematerial, such as Au, Ag, etc., to a thickness in a range between about5 nm to about 120 nm, such as about 100 nm.

Then, as shown in FIG. 8H, a sputtering method is used to form an uppermagnetic shield layer 16 and an additional insulating layer (alsolabeled as 21) between the back wiring layer 20 and the upper magneticshield layer 16.

The method described in FIGS. 8A-8H is representative of the formationof one embodiment of a multi-element magnetic head. Although twoelements 4, 5 are shown, it is possible to form more than two elementsin each read head, as would be understood by one of skill in the art,such as three four, 10, 16, 24, 32, etc.

According to another embodiment, a magnetic head may be formed inaccordance with another method, described with reference to FIGS. 9A-9H.

As shown in FIG. 9A, a lower magnetic shield layer 1 comprising NiFe,CoFe, or some other suitable material known in the art is provided. Thelower magnetic shield layer 1 may be provided by way of a film of Al₂O₃,MgO, etc., on an Al₂O₃—TiC wafer serving as a base body of a slider (notshown in the Figures). Then, for example, a sputtering method or someother suitable formation technique may be employed to deposit aninsulating layer 14 comprising alumina or some other suitable insultingmaterial thereon. The insulating layer 14 may have a thickness, in someapproaches, in a range from about 1 nm to about 10 nm, such as about 2nm. Next, a soft magnetic shield wiring underlayer 19 is formed usingany suitable formation technique known in the art, such as sputtering,to a thickness of between about 1 nm and about 10 nm, for example, 5 nm,which may comprise any suitable material, such as NiFe, CoFe, etc.

Next, a sputtering method or some other suitable formation technique maybe employed to fabricate a MR film 2 thereabove. The MR film 2 maycomprise any layers and materials known in the art. In one example, theMR film 2 may comprise at least a free layer, a barrier layer, and apinned layer. More specifically, the MR film 2 may comprise, forexample, a 1 nm Ta underlayer, a 5 nm IrMn AFM layer, a 2 nm CoFeBpinned layer, a MgO tunnel insulating film, and a free layer comprisinga 5 nm CoFeB/2 nm NiFe laminated film.

Next, as shown in FIG. 9B, a track pattern mask 3 is provided to form agap between later-formed elements. The track pattern mask extends fullfilm in the element height direction. The gap may be about equal to atrack width, such as from about 5 nm to about 30 nm. For example, a 20nm track width may be fabricated in the MR film 2 by spacer-type doublepatterning or some other suitable method known in the art. In thespacer-type double patterning, an ArF exposure apparatus, an ArF liquidimmersion exposure apparatus, or EUV may be utilized, along with anormal exposure and/or double patterning.

Next, as shown in FIG. 9C, using the track pattern mask 3 as a mask, theMR film 2 is etched using any suitable etching technique known in theart, such as via Ar ion milling, RIE, etc., to expose the insulatinglayer 14 and fabricate a first MR element 4 and a second MR element 5which comprise portions of the MR film 2 which remains after the etchingprocess.

Then, a refill layer 6 is formed using any suitable formation technique,such as a sputtering method. The refill layer 6 may have a thickness ina range from about 1 nm to about 30 nm, such as about 2 nm. Furthermore,the refill layer may comprise any suitable material, such as Al₂O₃, MgO,etc. Then, a magnetic domain control layer 7 is deposited using anysuitable deposition method, such as a LTS method having excellentlinearity, to a thickness in a range from about 5 nm to about 100 nm,such as about 13 nm. The magnetic domain control layer 7 may compriseany suitable material known in the art, such as CoPt among others.

Next, as shown in FIG. 9D, the track pattern mask 3 is removed bylift-off, CMP or some other suitable technique known in the art.

As shown in FIG. 9E, a height mask pattern 13 is provided above thefirst MR element 4 and the second MR element 5 to establish a heightfrom the media-facing surface in the element height direction in a rangefrom about 50 nm to about 1000 nm, such as about 500 nm. This heightmask pattern 13 is used as a mask to etch the magnetic domain controllayer 7, the refill layer 6, and the two elements 4, 5 using Ar ionmilling, RIE, or some other suitable technique, to expose the pinnedlayer of the elements 4, 5.

Next, as shown in FIG. 9F, a refill layer 21 is deposited above theetched portions of the structure using any technique known in the art,such as a sputtering method, to a thickness in a range from about 5 nmto about 30 nm, such as about 20 nm, which may comprise any suitablematerial known in the art, such as Al₂O₃. Then the height mask pattern13 is removed by lift-off, CMP, etc.

As shown in FIG. 9G, a wiring mask pattern is formed above the structureat the media-facing surface thereof, and some of the height refill layer21 is removed via etching at a rear end thereof in the element heightdirection, such as via Ar ion milling. Then, a back wiring layer 20 isformed behind the refill layer 21 in the element height direction usingany suitable method known in the art from a suitable conductivematerial, such as Au, Ag, etc., to a thickness in a range between about5 nm to about 120 nm, such as about 100 nm. The back wiring layer 20 isconfigured to electrically communicate with the MR elements 4, 5, in oneembodiment.

Then, as shown in FIG. 9H, a sputtering method is used to form an uppermagnetic shield layer 16 and an additional insulating layer (alsolabeled as 21) between the back wiring layer 20 and the upper magneticshield layer 16.

The method described in FIGS. 9A-9H is representative of the formationof one embodiment of a multi-element magnetic head. Although twoelements 4, 5 are shown, it is possible to form more than two elementsin each read head, as would be understood by one of skill in the art,such as three four, 10, 16, 24, 32, etc.

According to another embodiment, a magnetic head may be formed inaccordance with another method, described with reference to FIGS.10A-10G.

As shown in FIG. 10A, a lower magnetic shield layer 1 comprising NiFe,CoFe, or some other suitable material known in the art is provided. Thelower magnetic shield layer 1 may be provided by way of a film of Al₂O₃,MgO, etc., on an Al₂O₃—TiC wafer serving as a base body of a slider (notshown in the Figures). Next, a sputtering method or some other suitableformation technique may be employed to fabricate a MR film 2 thereabove.In one approach, an insulating film (not shown) may be provided betweenthe MR film 2 and the lower magnetic shield layer 1, the insulating filmcomprising alumina and having a thickness between about 1 nm and about10 nm, such as about 2 nm, in one approach. The MR film 2 may compriseany layers and materials known in the art. In one example, the MR film 2may comprise at least a free layer, a barrier layer, and a pinned layer.More specifically, the MR film 2 may comprise, for example, a 1 nm Taunderlayer, a 5 nm IrMn AFM layer, a 2 nm CoFeB pinned layer, a MgOtunnel insulating film, and a free layer comprising a 5 nm CoFeB/2 nmNiFe laminated film.

Then, a height mask pattern 13 is provided above the MR film 2 toestablish a height from the media-facing surface in the element heightdirection in a range from about 50 nm to about 1000 nm, such as about500 nm. This height mask pattern 13 is used as a mask to etch the MRfilm 2 using Ar ion milling, RIE, or some other suitable technique, toexpose the lower magnetic shield layer 1.

Next, a refill layer 21 is deposited above the etched portions of thestructure using any technique known in the art, such as a sputteringmethod, to a thickness in a range from about 5 nm to about 30 nm, suchas about 20 nm, which may comprise any suitable material known in theart, such as Al₂O₃.

Then, as shown in FIG. 10B, the height mask pattern 13 is removed bylift-off, CMP, etc.

Next, as shown in FIG. 10C, an upper wiring layer 15 comprising anysuitable material known in the art is deposited using any knowntechnique, such as sputtering, in a thickness from about 1 nm to about10 nm, such as about 5 nm. The upper wiring layer 15 may comprise Cr orthe like, or NiFe, CoFe, etc. to allow the layer to also be used as amagnetic shield layer and a wiring layer. Next, an upper insulating film12 is formed above the upper wiring layer 15 using any known formationtechnique, such as sputtering, to a thickness of about 1 nm to about 10nm, such as about 2 nm. The upper insulating film 12 may comprise anysuitable insulating material, such as Al₂O₃, MgO, etc.

Moreover, as shown in FIG. 10D, a track pattern mask 3 is provided abovethe upper insulating film 12 to form a gap between later-formedelements. The track pattern mask extends full film in the element heightdirection. The gap may be about equal to a track width, such as fromabout 5 nm to about 30 nm. For example, a 20 nm track width may befabricated in the MR film 2 by spacer-type double patterning or someother suitable method known in the art. In the spacer-type doublepatterning, an ArF exposure apparatus, an ArF liquid immersion exposureapparatus, or EUV may be utilized, along with a normal exposure and/ordouble patterning. In this approach, the track pattern mask 3 may beemployed as a height direction wiring pattern.

Next, as shown in FIG. 10E, using the track pattern mask 3 as a mask,the MR film 2 is etched using any suitable etching technique known inthe art, such as via Ar ion milling, reactive ion etching (RIE), etc.,to expose the lower magnetic shield layer 1 (or insulating layer that isnot shown) and fabricate a first MR element 4 and a second MR element 5which comprise portions of the MR film 2 which remains after the etchingprocess.

Then, a refill layer 6 is formed using any suitable formation technique,such as a sputtering method. The refill layer 6 may have a thickness ina range from about 1 nm to about 30 nm, such as about 2 nm. Furthermore,the refill layer may comprise any suitable material, such as Al₂O₃, MgO,etc. Then, a magnetic domain control layer 7 is deposited using anysuitable deposition method, such as a LTS method having excellentlinearity, to a thickness in a range from about 5 nm to about 100 nm,such as about 13 nm. The magnetic domain control layer 7 may compriseany suitable material known in the art, such as CoPt among others.

Next, as shown in FIG. 10F, the track pattern mask 3 is removed bylift-off, CMP or some other suitable technique known in the art. Then, awiring mask pattern is provided above the first MR element 4 and thesecond MR element 5 to establish a height from the media-facing surfacein the element height direction in a range from about 50 nm to about1000 nm, such as about 500 nm. This wiring mask pattern is used to forma back wiring layer 20 behind the upper insulating film 12 in theelement height direction using any suitable method known in the art froma suitable conductive material, such as Au, Ag, etc., to a thickness ina range between about 5 nm to about 120 nm, such as about 100 nm. Theupper wiring layer 15 is configured to electrically communicate with theback wiring layer 20 in one embodiment. Also, the back wiring layer 20is configured to electrically communicate with the MR elements 4, 5, inanother embodiment.

Then, as shown in FIG. 10G, a sputtering method is used to form an uppermagnetic shield layer 16 and a wire separation insulating layer 22between the back wiring layer 20 and the upper magnetic shield layer 16.Any suitable material as known in the art may be used for the uppermagnetic shield layer 16, such as NiFe, CoFe, etc., and the wireseparation insulating layer 22, such as alumina, MgO, etc.

The method described in FIGS. 10A-10G is representative of the formationof one embodiment of a multi-element magnetic head. Although twoelements 4, 5 are shown, it is possible to form more than two elementsin each read head, as would be understood by one of skill in the art,such as three four, 10, 16, 24, 32, etc.

According to another embodiment, a magnetic head may be formed inaccordance with another method, described with reference to FIGS.11A-11G.

As shown in FIG. 11A, a lower magnetic shield layer 1 comprising NiFe,CoFe, or some other suitable material known in the art is provided. Thelower magnetic shield layer 1 may be provided by way of a film of Al₂O₃,MgO, etc., on an Al₂O₃—TiC wafer serving as a base body of a slider (notshown in the Figures). Next, a sputtering method or some other suitableformation technique may be employed to fabricate a MR film 2 thereabove.In one approach, an insulating film (not shown) may be provided betweenthe MR film 2 and the lower magnetic shield layer 1, the insulating filmcomprising alumina and having a thickness between about 1 nm and about10 nm, such as about 2 nm, in one approach. The MR film 2 may compriseany layers and materials known in the art. In one example, the MR film 2may comprise at least a free layer, a barrier layer, and a pinned layer.More specifically, the MR film 2 may comprise, for example, a 1 nm Taunderlayer, a 5 nm IrMn antiferromagnetic (AFM) layer, a 2 nm CoFeBpinned layer, a MgO tunnel insulating film, and a free layer comprisinga 5 nm CoFeB/2 nm NiFe laminated film.

Then, a height mask pattern 13 is provided above the MR film 2 toestablish a height from the media-facing surface in the element heightdirection in a range from about 50 nm to about 1100 nm, such as about500 nm. This height mask pattern 13 is used as a mask to etch the MRfilm 2 using Ar ion milling, RIE, or some other suitable technique, toexpose the lower magnetic shield layer 1.

Next, a refill layer 21 is deposited above the etched portions of thestructure using any technique known in the art, such as a sputteringmethod, to a thickness in a range from about 5 nm to about 30 nm, suchas about 20 nm, which may comprise any suitable material known in theart, such as Al₂O₃.

Then, as shown in FIG. 11B, the height mask pattern 13 is removed bylift-off, CMP, etc.

Next, as shown in FIG. 11C, an upper wiring layer 15 comprising anysuitable material known in the art is deposited using any knowntechnique, such as sputtering, in a thickness from about 1 nm to about10 nm, such as about 5 nm. The upper wiring layer 15 may comprise Cr orthe like, or NiFe, CoFe, etc. to allow the layer to also be used as amagnetic shield layer and a wiring layer. Next, an upper insulating film12 is formed above the upper wiring layer 15 using any known formationtechnique, such as sputtering, to a thickness of about 1 nm to about 10nm, such as about 2 nm. The upper insulating film 12 may comprise anysuitable insulating material, such as Al₂O₃, MgO, etc.

Moreover, as shown in FIG. 11D, a track pattern mask 3 is provided toform a gap between later-formed elements. The track pattern mask extendsfull film in the element height direction. The gap may be about equal toa track width, such as from about 5 nm to about 30 nm. For example, a 20nm track width may be fabricated in the MR film 2 by spacer-type doublepatterning or some other suitable method known in the art. In thespacer-type double patterning, an ArF exposure apparatus, an ArF liquidimmersion exposure apparatus, or EUV may be utilized, along with anormal exposure and/or double patterning. In this approach, the trackpattern mask 3 may be employed as a height direction wiring pattern.

Next, as shown in FIG. 11E, using the track pattern mask 3 as a mask,the MR film 2 is etched using any suitable etching technique known inthe art, such as via Ar ion milling, RIE, etc., to expose the lowermagnetic shield layer 1 (or insulating layer that is not shown) andfabricate a first MR element 4 and a second MR element 5 which compriseportions of the MR film 2 which remains after the etching process.

Then, a refill layer 6 is formed using any suitable formation technique,such as a sputtering method. The refill layer 6 may have a thickness ina range from about 1 nm to about 30 nm, such as about 2 nm. Furthermore,the refill layer may comprise any suitable material, such as Al₂O₃, MgO,etc. Then, a magnetic side shield layer 17 is deposited using anysuitable deposition method, such as a LTS method having excellentlinearity, to a thickness in a range from about 5 nm to about 100 nm,such as about 13 nm. The magnetic side shield layer 17 may comprise anysuitable material known in the art, such as NiFe among others.

Next, as shown in FIG. 11F, the track pattern mask 3 is removed bylift-off, CMP or some other suitable technique known in the art. Then, awiring mask pattern is provided above the first MR element 4 and thesecond MR element 5 to establish a height from the media-facing surfacein the element height direction in a range from about 50 nm to about1100 nm, such as about 500 nm. This wiring mask pattern is used to forma back wiring layer 20 behind the upper insulating film 12 in theelement height direction using any suitable method known in the art froma suitable conductive material, such as Au, Ag, etc., to a thickness ina range between about 5 nm to about 120 nm, such as about 100 nm.

Then, as shown in FIG. 11G, a sputtering method is used to form an uppermagnetic shield layer 16 and a wire separation insulating layer 22between the back wiring layer 20 and the upper magnetic shield layer 16.Any suitable material as known in the art may be used for the uppermagnetic shield layer 16, such as NiFe, CoFe, etc., and the wireseparation insulating layer 22, such as alumina, MgO, etc.

The method described in FIGS. 11A-11G is representative of the formationof one embodiment of a multi-element magnetic head. Although twoelements 4, 5 are shown, it is possible to form more than two elementsin each read head, as would be understood by one of skill in the art,such as three four, 10, 16, 24, 32, etc.

According to another embodiment, a magnetic head may be formed inaccordance with another method, described with reference to FIGS.12A-12G.

As shown in FIG. 12A, a lower magnetic shield layer 1 comprising NiFe,CoFe, or some other suitable material known in the art is provided. Thelower magnetic shield layer 1 may be provided by way of a film of Al₂O₃,MgO, etc., on an Al₂O₃—TiC wafer serving as a base body of a slider (notshown in the Figures). Next, a sputtering method or some other suitableformation technique may be employed to fabricate a MR film 2 thereabove.In one approach, an insulating film (not shown) may be provided betweenthe MR film 2 and the lower magnetic shield layer 1, the insulating filmcomprising alumina and having a thickness between about 1 nm and about10 nm, such as about 2 nm, in one approach. The MR film 2 may compriseany layers and materials known in the art. In one example, the MR film 2may comprise at least a free layer, a barrier layer, and a pinned layer.More specifically, the MR film 2 may comprise, for example, a 1 nm Taunderlayer, a 5 nm IrMn AFM layer, a 2 nm CoFeB pinned layer, a MgOtunnel insulating film, and a free layer comprising a 5 nm CoFeB/2 nmNiFe laminated film.

Then, a height mask pattern 13 is provided above the MR film 2 toestablish a height from the media-facing surface in the element heightdirection in a range from about 50 nm to about 1000 nm, such as about500 nm. This height mask pattern 13 is used as a mask to etch the MRfilm 2 using Ar ion milling, RIE, or some other suitable technique, toexpose the lower magnetic shield layer 1.

Next, a refill layer 21 is deposited above the etched portions of thestructure using any technique known in the art, such as a sputteringmethod, to a thickness in a range from about 5 nm to about 30 nm, suchas about 20 nm, which may comprise any suitable material known in theart, such as Al₂O₃.

Then, as shown in FIG. 12B, the height mask pattern 13 is removed bylift-off, CMP, etc.

Next, as shown in FIG. 12C, an upper wiring layer 15 comprising anysuitable material known in the art is deposited using any knowntechnique, such as sputtering, in a thickness from about 1 nm to about10 nm, such as about 5 nm. The upper wiring layer 15 may comprise Cr orthe like, or NiFe, CoFe, etc. to allow the layer to also be used as amagnetic shield layer and a wiring layer. Next, an upper insulating film12 is formed above the upper wiring layer 15 using any known formationtechnique, such as sputtering, to a thickness of about 1 nm to about 10nm, such as about 2 nm. The upper insulating film 12 may comprise anysuitable insulating material, such as Al₂O₃, MgO, etc.

Moreover, as shown in FIG. 12D, a track pattern mask 3 is provided abovethe upper insulating film 12 to form a gap between later-formedelements. The track pattern mask extends full film in the element heightdirection. The gap may be about equal to a track width, such as fromabout 5 nm to about 30 nm. For example, a 20 nm track width may befabricated in the MR film 2 by spacer-type double patterning or someother suitable method known in the art. In the spacer-type doublepatterning, an ArF exposure apparatus, an ArF liquid immersion exposureapparatus, or EUV may be utilized, along with a normal exposure and/ordouble patterning. In this approach, the track pattern mask 3 may beemployed as a height direction wiring pattern. As shown, the trackpattern mask 3 comprises four portions, but may include more or lessbased on a number of elements to be formed in the head.

Next, as shown in FIG. 12E, using the track pattern mask 3 as a mask,the MR film 2 is etched using any suitable etching technique known inthe art, such as via Ar ion milling, RIE, etc., to expose the lowermagnetic shield layer 1 and fabricate a plurality of MR elements 23which comprise portions of the MR film 2 which remains after the etchingprocess.

Then, a refill layer 6 is formed using any suitable formation technique,such as a sputtering method. The refill layer 6 may have a thickness ina range from about 1 nm to about 30 nm, such as about 2 nm. Furthermore,the refill layer may comprise any suitable material, such as Al₂O₃, MgO,etc. Then, a magnetic side shield layer 17 is deposited using anysuitable deposition method, such as a LTS method having excellentlinearity, to a thickness in a range from about 5 nm to about 100 nm,such as about 13 nm. The magnetic side shield layer 17 may comprise anysuitable material known in the art, such as NiFe among others.

Next, as shown in FIG. 12F, the track pattern mask 3 is removed bylift-off, CMP or some other suitable technique known in the art. Then,as shown in FIG. 12G, an upper magnetic shield layer 16, a wireseparation insulating layer 22, and a back wiring layer 20 are formed insequence in the element height direction from the media-facing surfacebackward using any suitable method known in the art. The back wiringlayer 20 comprises any suitable conductive material, such as Au, Ag,etc., and is formed to a thickness in a range between about 5 nm toabout 120 nm, such as about 100 nm.

The method described in FIGS. 12A-12G is representative of the formationof one embodiment of a multi-element magnetic head. Although four MRelements 23 are shown, it is possible to form more than four elements ineach read head, as would be understood by one of skill in the art, suchas three 8, 10, 16, 24, 32, etc.

It should be noted that methodology presented herein for at least someof the various embodiments may be implemented, in whole or in part, incomputer hardware, software, by hand, using specialty equipment, etc.,and combinations thereof.

The multi-element magnetic read head described herein according tovarious embodiments allows for signals of the included elements to beseparately extracted along the element height direction, and facilitatesa narrowing of the read gap width and an increase in the recordingdensity possible for a magnetic medium used in conjunction with themulti-element magnetic read head.

While various embodiments have been described above, it should beunderstood that they have been presented by way of example only, and notlimitation. Thus, the breadth and scope of an embodiment of the presentinvention should not be limited by any of the above-described exemplaryembodiments, but should be defined only in accordance with the followingclaims and their equivalents.

What is claimed is:
 1. A magnetic head, comprising: at least onemagnetoresistive (MR) element, the at least one MR element extending inan element height direction away from a media-facing surface of themagnetic head; and at least one back wiring layer positioned above atleast one lower layer of the at least one MR element at a position awayfrom the media-facing surface of the magnetic head in the element heightdirection, wherein the at least one back wiring layer is configured toelectrically communicate with the at least one MR element.
 2. Themagnetic head as recited in claim 1, wherein each of the at least one MRelement comprises a pinned layer, a barrier layer positioned above thepinned layer, and a free layer positioned above the barrier layer, andwherein the at least one back wiring layer is configured to separatelyextract a signal from its respective MR element during a read operation.3. The magnetic head as recited in claim 1, wherein the magnetic headcomprises a plurality of MR elements.
 4. The magnetic head as recited inclaim 1, further comprising: a lower shield layer positioned below theat least one MR element at a media-facing surface of the magnetic head;and an upper shield layer positioned above the at least one MR element,the upper shield layer being configured to electrically communicate withthe at least one MR element.
 5. The magnetic head as recited in claim 4,further comprising an insulating layer positioned between the lowershield layer and the at least one MR element, wherein the upper shieldlayer is configured to act as an upper electrode for the at least one MRelement.
 6. The magnetic head as recited in claim 5, further comprisinga magnetic domain control layer positioned on both sides of each of theat least one MR element in a cross-track direction, wherein the magneticdomain control layer is separated from each of the at least one MRelement by an insulating layer.
 7. The magnetic head as recited in claim5, further comprising an insulating layer positioned between the uppershield layer and the back wiring layer, wherein a portion of each of theat least one MR element which extends away from the media-facing surfaceof the magnetic head in the element height direction is configured toact as a lower electrode for its respective MR element.
 8. The magnetichead as recited in claim 5, further comprising a wiring underlayerpositioned below each of the at least one MR element, the wiringunderlayer being configured to act as a lower electrode for itsrespective MR element, wherein the wiring underlayer comprises Cr, NiFe,and/or CoFe.
 9. The magnetic head as recited in claim 4, furthercomprising an upper wiring layer positioned above each of the at leastone MR element at the media-facing surface of the magnetic head andextending in the element height direction away from the media-facingsurface of the magnetic head, wherein the upper wiring layer isconfigured to electrically communicate with the back wiring layer, andwherein the lower shield layer is configured to act as a lower electrodefor the at least one MR element.
 10. The magnetic head as recited inclaim 9, further comprising a magnetic domain control layer positionedon both sides of each of the at least one MR element in a cross-trackdirection, wherein the magnetic domain control layer is separated fromeach of the at least one MR element by an insulating layer.
 11. Themagnetic head as recited in claim 9, further comprising a magnetic sideshield layer positioned on both sides of each of the at least one MRelement in a cross-track direction, wherein the magnetic side shieldlayer is separated from each of the at least one MR element by aninsulating layer.
 12. A magnetic data storage system, comprising: atleast one magnetic head as recited in claim 1; a magnetic medium; adrive mechanism for passing the magnetic medium over the at least onemagnetic head; and a controller electrically coupled to the at least onemagnetic head for controlling operation of the at least one magnetichead.
 13. A magnetic head, comprising: at least one magnetoresistive(MR) element positioned at a media-facing surface of the magnetic head,a lower portion of the at least one MR element extending in an elementheight direction away from the media-facing surface of the magnetic headfarther than an upper portion of the at least one MR element; at leastone back wiring layer positioned behind the upper portion of the atleast one MR element in the element height direction and above the lowerportion of the at least one MR element, wherein the at least one backwiring layer is configured to electrically communicate with the at leastone MR element; and an upper wiring layer positioned above the at leastone MR element at the media-facing surface of the magnetic head andextending in the element height direction away from the media-facingsurface of the magnetic head, the upper wiring layer being configured toelectrically communicate with the back wiring layer.
 14. The magnetichead as recited in claim 13, wherein each of the at least one MR elementcomprises a pinned layer, a barrier layer positioned above the pinnedlayer, and a free layer positioned above the barrier layer, wherein theupper portion of each of the at least one MR element comprises at leastthe free layer, and wherein the at least one back wiring layer isconfigured to separately extract a signal from its respective MR elementduring a read operation.
 15. A method for forming a magnetic head, themethod comprising: forming at least one magnetoresistive (MR) element,the at least one MR element extending in an element height directionaway from a media-facing surface of the magnetic head; and forming atleast one back wiring layer positioned above at least one lower layer ofthe at least one MR element at a position away from the media-facingsurface of the magnetic head in the element height direction, whereinthe at least one back wiring layer is configured to electricallycommunicate with the at least one MR element.
 16. The method as recitedin claim 15, further comprising: forming a lower shield layer below theat least one MR element; and forming an upper shield layer above the atleast one MR element, the upper shield layer being configured toelectrically communicate with the at least one MR element, whereinforming the at least one MR element further comprises, for each of theat least one MR element: forming a pinned layer; forming a barrier layerabove the pinned layer; and forming a free layer above the barrierlayer, the free layer being configured to sense data on a magneticmedium passed across the media-facing surface of the magnetic head, andwherein the at least one back wiring layer is configured to separatelyextract a signal from its respective MR element during a read operation.17. The method as recited in claim 16, further comprising forming aninsulating layer between the lower shield layer and the at least one MRelement, wherein a portion of each of the one MR element which extendsaway from the media-facing surface of the magnetic head is configured toact as a lower electrode for its respective MR element.
 18. The methodas recited in claim 17, further comprising forming a magnetic domaincontrol layer on both sides of each of the one MR element in across-track direction, wherein the magnetic domain control layer isseparated from each of the one MR element by an insulating layer. 19.The method as recited in claim 16, further comprising forming aninsulating layer between the upper shield layer and the at least oneback wiring layer.
 20. The method as recited in claim 15, furthercomprising forming a wiring underlayer below the at least one MRelement, the wiring underlayer being configured to act as a lowerelectrode for the at least one MR element, wherein the wiring underlayercomprises Cr, NiFe, and/or CoFe.